Impact of processing (toasting and fermentation) on the proximate, anti-nutrient and mineral composition of sickle pod (Senna obtusifolia) seeds

Muhammad Abdulkadir, Danladi Amadu Ameh, Humphrey Chuks Nzelibe, Shehu Muhammad Hassan and Aliyu Mansir

Keywords: Anti-nutritional factors, fermentation, minerals contents, proximate analysis, Senna obtusifolia seeds and toasting


Background: The plant Senna obtusifolia is of the kingdom plantae, family fabaceae, found Northern Nigeria. It uses are in management of dysentery and diarrhea. Objective: To propose an effective processing method for safe utilization of sickle pod seeds. Methods: For five days, S. obtusifolia seeds were fermented using Aspergillus niger at room temperature.S. obtusifolia seeds were also toasted for 10 minutes at 85°C. Result:7.45 mg/100g moisture, 33.33 mg/100g crude protein, 17.25 mg/100g lipid, 9.49 mg/100g dietary fiber, 4.50 mg/100g ash, 37.99 mg/100g nitrogen free extract were all found in raw S. obtusifolia seeds. Raw S. obtusifolia seeds had 3.95 mg/100g tannins, 3.74 mg/100g phytates, 2.13 mg/100g oxalates and 2.62 mg/100g saponins, 11.23 TUI/mg trypsin inhibitor and 5.77 IC50 (mg/mL) alpha amylase inhibitor. Fermentation increased the crude protein of S. obtusifolia seeds but reduced NFE, moisture, lipid and dietary fibre similar to toasting plus fermentation. Toasting reduced moisture, dietary fibre, crude protein but increased lipid, ash and NFE. Fermentation reduced the tannins by 38 %, phytates by 84 %, oxalates by 36 %, saponins by 37 %, trypsin inhibitor by 12 % and α-amylase inhibitor to 6.40 IC50 (mg/mL) while toasting reduced tannins by 63%, phytates by 89%, oxalates by 61 %, saponins by 66 %, trypsin inhibitor by 40 % and α-amylase inhibitor to 13.05 IC50 (mg/mL). Toasting/fermentation reduced tannins by 70 %, phytates by 93%, oxalates by 54 %, saponins by 91 %, trypsin inhibitor by 43 % and α-amylase inhibitor to 19.54 IC50 (mg/mL). Fermentation reduced all the total mineral contents, toasting increased Fe, Mg, K and Na but reduced Ca and Zn. Toasting/fermentation reduced Ca, Mg, Zn, K and Na but increased Fe. Conclusion: The proximate composition, anti-nutrients, and mineral content of S. obtusifolia seeds were all influenced by fermentation.